(a) Technical Field of the Invention
The present invention relates to a voltage transformer, which converts AC or DC as input power source to a preset voltage.
(b) Description of the Prior Art
Most electrical appliances are generally provided with a voltage transformer so as to change voltage at 110 V or 220 V for DC power source.
As shown in FIG. 1, the conventional transformer includes a transformer coil a, a rectifying element b and a voltage stabilizing element c. The transformer coil converts the AC 110 V or AC 220 V of the input terminal to smaller voltage AC by means of magnetic induction of the transformer coil, and via the bridge-type rectifying element b, the AC is transformed to DC. A capacitor is connected in series so as to stabilize the output voltage.
Although this conventional transformer has the advantage of having a simple structure, the following drawbacks are commonly found:
Due to the components, such as the transformer coil, etc, the size of the transformer cannot be made into a smaller size device.
Conventional transformer does not applicable to AC and DC.
Vibration, distortion, and hear are produced in the conventional transformer.
Heat energy is evolved and the housing of the transformer may be damaged after a period of use.
If the input voltage is not stable, the output voltage from the transformer may be too great that electrical appliances may be damaged.
Accordingly, it is an object of the present invention to provide a voltage transformer AC and DC, wherein electronic parts are provided on a circuit board so as to lower the voltage of the power source and the vibration and noise of the conventional transformer are not found, and the AC and DC voltage are used as input voltage, and thus, the size and weigh of the transformer are reduced.
Yet another object of the present invention is to provide a voltage transformer AC and DC, wherein the essential electrical components produce low heat energy and their workability are stable, ensuring the stability of the output voltage, with no distortion and surge.
The foregoing object and summary provide only a brief introduction to the present invention. To fully appreciate these and other objects of the present invention as well as the invention itself, all of which will become apparent to those skilled in the art, the following detailed description of the invention and the claims should be read in conjunction with the accompanying drawings. Throughout the specification and drawings identical reference numerals refer to identical or similar parts.
Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.